1. Field of the Invention.
This invention relates to a medical device used to connect to another medical device. More particularly, the subject invention relates to a blunt needle connector that can be safely, easily, and securely locked in communication with a fitting of an intravenous administration set.
2. Description of the Prior Art.
Intravenous sets are widely use in the prior art to provide intravenous fluid communication with a patient. The prior art intravenous sets include a needle cannula for insertion into a vein of the patient. The needle cannula communicates with one end of a flexible plastic tube, while the opposite end of the tube is connectable to a flexible bag or bottle containing the fluid to be administered to the patient.
A prior art intravenous set may also include a fitting to which a hypodermic syringe may be used for administering parenteral drugs to a patient. One example of such a fitting is known as a "straight-site". A straight-site is a relatively straight fitting, typically made from a plastic material, and includes an injection inlet carrying medication from a source in an outlet portion affixed to a tube which delivers the parenteral drug to the patient. The injection inlet usually includes a diaphragm portion, typically made of rubber or a similar compound, which can be pierced by the needle cannula of the syringe carrying the parenteral drug. The diaphragm portion, normally configured to be fitted in a fluid-tight manner to the injection inlet, typically defines a lip portion which protrudes from the stresses of the injection inlet along the outer circumference of the injection inlet.
Another example of such an intravenous fitting is known in the art as a "Y-site". A Y-site is typically a Y-shaped plastic fitting having an inlet leg, an outlet leg, and an injection leg. Like the straight-site fitting, the injection leg of the Y-site is also covered by a diaphragm defining a lip portion. The diaphragm can be pierced by the needle cannula of a syringe carrying the parenteral drug. The injection leg and the outlet leg of the prior art Y-site typically are co-linear with one another. The inlet leg typically is aligned at approximately 30 degrees to 45 degrees to the injection leg.
In use, a needle cannula of a hypodermic syringe carrying the parenteral drug to be administered is pierced through the membrane or septum of the injection inlet of the straight-site or injection leg of the Y-site. A hypodermic syringe is used in the standard manner to inject a selected dose of the parenteral drug into the injection leg. The drug is then transported to the patient by the fluid flowing from the injection inlet or leg and through the outlet portion or leg and toward the patient. A hypodermic needle is often used for introducing medication through the septum. For purposes of illustration but not of limitation, the medication delivery is implemented through the septum using a syringe. However, it will be understood that the delivery is not so limited and that many fluid delivery devices can be used to provide fluid to the needle which pierces or passes through the septum.
The potential for accidental needle sticks is further reduced by prior art needle cannula having a rigid generally cylindrical shield mounted concentrically around the needle cannula. The shield defines a diameter large enough to telescope over an injection inlet or leg of the intravenous set as the needle cannula enters the fitting. Some such shields are provided with at least one axial extended opening for receiving the inlet leg of a Y-site as the remaining portions of the shield are telescoped over the injection leg.
Although prior art protective shields as described above, can reduce the probability of accidental needle sticks, the open end of the axially extended openings still offer a potential for contact with the needle cannula. The nurse or other medical personnel utilizing the shield must manually manipulate the device to secure the shield to the injection inlet. Connecting the shield to the inlet is oftentimes done with tape. Additionally, a source of intravenous fluid intended for connection to the intravenous fitting can be accidentally disengaged either before its initial use or between successive uses. Thus, there can be a potential for both contamination of the needle cannula and/or loss of medication which can potentially be fatal to the patient.
Prior art blunt needle connectors designed to prevent accidental needle sticks oftentimes require the needle to be recesed within some protective shield. This recess of the needle cannula presents a problem of aligning the connector to the intravenous fitting. Connectors that provide threads in order to align the connector with the intravenous fitting require twisting. This twisting often results in the twisting of the intravenous line which is not preferred by the nurse or other medical personnel. Additionally, prior art blunt needle connectors are sometimes difficult to distinguish between when the connector is in the open (unlocked) position and the closed (locked) position. There is a need for some indicator to notify the user that the latch was secured to the intravenous fitting or port.